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Mr. Yaniger designed a phono preamplifier
dubbed "His Master's Noise" and published it on
www.diyaudio.com.
I decided to make a printed circuit board so that other DIYr's
could assemble the preamplifier and power supply. To make life
a bit easier, a PDF of the web-article is linked
HERE |
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This "pre-pre" is very nice indeed. A
moving coil step up transformer is used to drive the D3a.
In the example shown here, a Sowter 8055 transformer is used.
Other units from Cinemag or Jensen could used as well. Very
low distortion, very low noise. The printed circuit
boards I had fabricated measure approximately 10.0 by 8.4
inches. |
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Originally, I had some prototype boards
made to make sure that I got most everything correct. A
picture of the proto appears below: |
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I mounted this prototype in the cabinet of
an Eico signal generator which was gathering dust. The
chassis is actually much stiffer than conventional aluminum
cabinets and is steel, affording a measure of isolation of the
line frequency noise from the amplifier. |
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prototypes formed the basis of final production boards
which I've offered at cost through the Tech-DIY LLC
webstore. An unfinished board is shown below: |
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receiving the boards I realized that there was a mistake
on the silk screen. The orientation for Bridge
Rectifier D-11 is incorrect. The correct
orientation is shown in the photograph below: |
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explicitly specify where the center tap of the power
transformer should be connected. While it should
be obvious, I provide the following illustration to make
matters clear: |
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